Struct mmtkvdb::EnvRw

pub struct EnvRw { /* private fields */ }

Read-write handle for accessing environment that stores key-value databases

An environment can be opened using EnvBuilder.

The methods for read-only access are accessible through the Env trait (which is implemented by EnvRo and EnvRw). Methods for write access, however, are available directly on the EnvRw struct.

Use Env::open_db or EnvRw::create_db to retrieve database handles and EnvRw::txn_rw to start a read-write transaction.

It’s also possible to create a read-only handle from a read-write handle by invoking Env::clone_ro.

Implementations

impl EnvRw

pub fn nestable_txns(&self) -> bool

Check if transactions are nestable

See TxnRw::nested.

pub unsafe fn create_db<K, V, C>( &mut self, options: &DbSpec<K, V, C> ) -> Result<Db<K, V, C>>where K: ?Sized + Storable, V: ?Sized + Storable, C: Constraint,

Open database in environment and create if non-existing

Safety

• If a database exists already, it must have been created with compatible options.
• Implementation of Storable for the used keys and values must behave the same as when the database was created.

pub fn drop_db<K, V, C>(&mut self, db: Db<K, V, C>) -> Result<()>where K: ?Sized + Storable, V: ?Sized + Storable, C: Constraint,

Delete database in environment

This method panics if there are clones of the Db handle. Use TxnRw::delete_all to only delete the contents of the database.

pub fn txn_rw(&mut self) -> Result<TxnRw<'_>>

Start read-write transaction

Trait Implementations

impl AsRef<EnvRo> for EnvRw

fn as_ref(&self) -> &EnvRo

Converts this type into a shared reference of the (usually inferred) input type.

impl Debug for EnvRw

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Env for EnvRw

fn txn_ro(&self) -> Result<TxnRo<'_>>

Start read-only transaction

fn max_keysize(&self) -> usize

Get maximum size of keys and duplicate data

fn valid_keysize<'kr, K, KRef>(&self, key: KRef) -> boolwhere K: ?Sized + Storable + 'kr, KRef: StorableRef<'kr, K>,

Checks if key or duplicate data has valid size

unsafe fn open_db<K, V, C>( &self, options: &DbSpec<K, V, C> ) -> Result<Db<K, V, C>>where K: ?Sized + Storable, V: ?Sized + Storable, C: Constraint,

Open database in environment

fn clear_stale_readers(&self) -> Result<usize>

Clear stale readers

fn as_env_ro(&self) -> &EnvRo

Reference conversion to EnvRo

fn clone_ro(&self) -> EnvRo

Clone as EnvRo

impl EnvRef for &mut EnvRw

unsafe fn open_or_create_db<K, V, C>( &mut self, options: &DbSpec<K, V, C> ) -> Result<Db<K, V, C>>where K: Storable + ?Sized, V: Storable + ?Sized, C: Constraint,

Open database in environment and, if possible, create if non-existing

impl Hash for EnvRw

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq<EnvRw> for EnvRw

fn eq(&self, other: &EnvRw) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for EnvRw

impl StructuralEq for EnvRw

impl StructuralPartialEq for EnvRw